Example embodiments relate to a semiconductor device and a method of operating the same, and more particularly, to a precharge operation for a semiconductor device.
In general, a semiconductor memory device is used as a storage medium of a main memory. Examples of the semiconductor memory device include a read only memory (ROM) and a random access memory (RAM).
ROM is a memory that can only perform a read operation, and although power supply is blocked, data recorded in the ROM is not erased. Examples of the ROM include a mask ROM, a programmable ROM (PROM), and an erasable programmable ROM (EPROM). Data stored in RAM can be changed by a user, and the RAM can store data by a writing operation. When power supply is blocked, data stored in the RAM may be all erased.
Examples of the RAM include a static RAM (SRAM) and a dynamic RAM (DRAM). SRAM retains recorded data while power is supplied, whereas DRAM must be periodically refreshed to retain the stored data. In particular, DRAM operates at a reduced voltage and at a high speed, and consumes less power due to a scaling-down process.
A sense amplifier included in a DRAM may sense the state of a memory cell included in the DRAM and amplify a signal generated according to a result of the sensing. However, in conventional DRAM, when a power supply voltage is low, a sensing margin is reduced, leading to an increase in a sensing duration and a reduction of sensing accuracy.